The United States and China are lashing out at Japanese Prime Minister Shinzo Abe for visiting a controversial shrine to pay his respects to soldiers who died in World War II.

Abe visited the Yasukuni shrine in Tokyo, which honors 2.5 million war dead, including many considered to be war criminals, according to The Hill.

The U.S. Embassy in Tokyo said, "Japan is a valued ally and friend. Nevertheless, the United States is disappointed that Japan's leadership has taken an action that will exacerbate tensions with Japan's neighbors."

China warned that the country's historically poor relationship with Japan could deteriorate even further following the first visit to the shrine by a Japanese prime minister in seven years.

"The Chinese government expresses its strong indignation over the behavior of the Japanese leader, which grossly tramples on the sentiment of the Chinese people and other Asian peoples victimized in the war," said Qin Gang, China’s foreign ministry spokesman.

National Public Radio also quoted Qin Gang as saying, "Japanese leaders are not only showing no moderation but have doubled their efforts and created a serious incident on historical issues. This poses a major political obstacle in the improvement of bilateral relations. Japan must take responsibility for all the consequences that this creates."

The tensions between China and Japan have been greatly enhanced in recent weeks over China's new air defense zones which incorporate air space that Japan also claims.

The visits by Japanese officials to the shrine have long been a contention with China, as well as with South Korea, due to Japan's brutal aggression in those countries during World War II.

Abe said after his Thursday visit," I prayed to pay respect for the war dead who sacrificed their precious lives and hoped that they rest in peace.

"Unfortunately, a Yasukuni visit has largely turned into a political and diplomatic issue. I have no intention to neglect the feelings of the people in China and South Korea."

The U.S. statement expressed hope that Japan and its neighbors would be able to put "sensitive issues" behind them "to promote cooperation in advancing our shared goals of regional peace and stability.”